How do we feed low-moisture corn silage?

By Dr. Darin Bremmer, Vita Plus regional sales manager
Parts of our market area saw intense rainfall and flooding in recent weeks, causing a delay in harvest until the fields can dry out.  Other parts saw the exact opposite and have dealt with severe drought for the better part of the growing season.

Both crop situations can result in low moisture levels and these producers will have to work through the unique challenges of harvesting low-moisture corn silage.  When it comes to properly harvesting and feeding dry corn silage, it helps to adjust harvest basics – such as kernel processing, chopping height and packing – to achieve a good fermentation.

Kernel processing
Kernel processing has improved in recent years, allowing corn to mature longer and improve corn silage starch quality.  With dry corn silage, it is best to shorten the length of cut to ensure good kernel processing.  Vita Plus consultants have tools to help you monitor kernel processing throughout the harvest process.

Chopping height
Chopping at heights between 12 to 20 inches can help compensate for the decline in fiber digestibility associated with harvesting corn at a later stage of maturity.  This results in a 5-percent increase in fiber digestibility and starch because the lowest portion of the stalk contains the least-digestible fiber.

Pack, pack, pack!
Packing is emphasized every year, but it is especially important with low-moisture corn silage because drier corn silage is harder to pack and remove oxygen.

During ideal chopping conditions, pack tractors can become overwhelmed with too much silage at a time.  Slow down and make sure you have enough pack-tractor weight on every part of the pile to ensure good packing density.

If moisture levels are severely low, a more finely processed corn silage could improve packing density because it doesn’t have as much ability to expand after compression, which reduces oxygen levels.  However, the ration will have to be balanced for adequate effective fiber during feedout.

Keep fermentation in mind
Oxygen needs to be removed for fermentation to occur and activate the lactic acid-producing bacteria to reduce pH and preserve the silage.  However, this can’t be accomplished without moisture.

Although it is more critical with dry corn silage, we recommend adding a reputable lactic acid-producing inoculant, such as Vita Plus Crop-N-Rich® forage inoculant, each year to reduce the risk of spoilage as much as possible and give the best opportunity for stable silage.

How will it feed?
The answer depends on how well you accomplished the previous points.  During feedout, watch manure starch levels.  High manure starch levels could indicate poor kernel processing and lead to digestive upsets.  Also, monitor mold, yeast, and mycotoxin counts because the longer the crop stood in the field, the more opportunity yeasts and molds had to grow, which can also negatively impact cow health.

Dry corn silage could also have stability issues due to yeasts and molds if too little is removed from the face.  It will help if you don’t remove excess plastic at the face and keep a sand bag or a row of tires on the edge to prevent oxygen from getting under the plastic.

Lastly, stay safe.  With the difficulty to pack dry corn silage, chances are greater for a collapse.

Contact your Vita Plus consultant if you have questions about this year’s crop.

This article was originally written for the January 10, 2017 issue of Hoard’s Dairyman.  A full version of the article can be found in the magazine.

About the author:  Dr. Darin Bremmer grew up on a farm in Shannon, Illinois. Af­ter high school, he attended the University of Wisconsin-Platteville and received a bachelor’s degree in animal science in 1993. From 1993 to 1995, he attended the University of Illinois and received a master’s in animal science with an em­phasis in ruminant nutrition. Bremmer then completed a Ph.D. in nutritional sciences with an emphasis in animal nutrition and a minor in dairy science from UW-Madison in De­cember 1999. In Dr. Grummer’s labora­tory at UW-Madison, Bremmer’s research focused on transition cows, studying ketosis and fatty liver. After completing his Ph.D., Bremmer worked for a major feed company as a dairy nutritionist and technical services manager in Wisconsin. In March 2003, he joined Vita Plus as part of the dairy nutrition and technical services team based in central Wisconsin and also works as a regional sales manager there.